Draftsman&#39;s triangle.



' symmetrical :intl eensin; considerable con- Lit) 4entren ierrnnr onine FREDERIC S. CBISIPW'N, 0F LFi'ILADELPHM-i., PENNSYLVANIA.

Applicate@ med nay e, iene. serial no. @$4,554.

To all 'whom it may] concern.lm

.Be it known that l, Fnnnneie fit e, eitizen ot' the United States, 'fesiwh2 111` Philadelphie, in the county et' Philadelphie and Stute. of Pennsylvania, have ins' 'wl l Certain new anni Useful linpievelnen in li'aftsinenls Triangles, et' which the tellew ingl is :i speeificzitien.

My invention relates to fli'nttsinfnfs '1 1 anglesy that is to say, to e fleviee for lin/11g; ont and measuring angles on the drawing hoard.

The prineipz-il object of my to provite 1 1 drawing instiinnent out and measuring angles, Winer :ingles which are multiples of lo n drawn with e single instrument instee requiring tho two triangles :is new inonly used for this "iaii'pose.

l :un aware that seteiril torres of instru niente han' heretofore been Lisefl for tile foregoing pnroose, but these instinn'ients Were more or less.inconvenient being` 1111- fusion in the use 01"' the sinne, :intl some types requiring the more important nnlagles 'to he drawn on the under side et the inst 1imenig which frequently causes inaeenreeies' wliieh :1re unpereeivefl :it the nie.

Ainvention eo'fiteinplnies fi thin .let piece o1" wood, hard. rnhher, Celluloid or other suitable ineterizih the Working erle et which :we v:111172.11ge(l at suitnlile en whereby the gflrnttsman een ley ont or n1 ure any :ingle which e ninltiple of lo with the greatest possible ense end comen ienee; -1

The nature .unil ehziraeteristio features oit my inventien willhe more readily limiet-- stoorl tt'ointhe following description taken l in connectie-n n1 the accompanying tlreW- ings tlnminp; part hereotv in wl1ieli- 4 .iignre l a plain View ot :1 fjlraftsinzms tiizingie einhotlying the 11min tentures of n iy -presen1t ieventieinI the :se heini;F shown in one position on the working elslje of a. T squnreblade orother sti-aight ed@ g sind il is a. similar View lm' 'with the slrmnent shonfn in another position.

Referring .to the (lriiwinggfsa in the psi tieulzirV embodiment of my invention there shown, the instrument comprises e thin liet piece of Wood:` herd ruliher, Celluloid er other suitable materiel'heaving sin Guten Working edges A, B, C?, D, E, and l?. 'The .edges Ae and B ere at right Vzingles or 909W@ :Letters iletenteel July le?, MM2;

:1t i111 angle or" 3100 (or 150)- to lt will be seen that all angles which are multiples ef i5 (with the exception of 75 te the horizentzil) may 4be use laid eut hy the iene'ith the l square in its normal the .instrument over on its other @temple mth the 'instrument m en as shown 111 Fig. the angle of in the 1e line by' 'the employment of the instrument so '16111' fleserilveietl, f1 i5@ line may be first leid ont. .1211111151 znr'hitrary or convenient loeetion enel by shitting the instrument to brine;

one of the edges A or B in zilineriient with.

the :ii'liitrziryirf 15 line before drawn end then sl'liltirigi the instrument alongthe straight eden which for the purpose of guitling is hroniz'ht into .conjunction with the edges (l :mtl IDN the 75 line may be drawn' :it the desired loeetion by using the respectiveother edge B or A as the case may he. This manner of using e triangle is Well known te these skilled in the art and need not he 'Frther elnhoretetl upon.

is hel'oi'e stated all of the :ingles which :1re multiples ot 11.5 may he drawn solely by the iise'of {hemmt/side edges of the instrunient7 vbut it will he not-ed that to (lo so results in the necessity of considerable manipulation ef the instrumentend straight edge for drewine the T50 lines "To obviate this la Y @eeh eti'ier 1 n al il entire instilnnent isprefei rien! about :i line bisecting the et angles of i650 to sind edges C,

he instrmnent :1s so fur described inliorizontnl may he drawn along' ,respectively While the twoy Y hy' using; the instrument to occupytion shown in Figs. and :2 or4 he flrziwn along the e'dge F,

ineonvenit-inee? :incl to renderthe instrument more eoi'wenient in other respects it is prefernbly cut out at its center und is provided with two interior working edges G and H which :ire :it un :ingle of 120O (or 2400) to ezieh othe` und at :ingles of l5o to the outside edges A und B respeetively, :it angles of 30" to the edges C und D respectively, und fit ungl'les o't 150 to the edges` E und F respeetively. By the employment of the inside edges G :ind H ot' the instrument in the position :is shown in Fig. l, the ingle of 75C to the horizontal muy be druwn by the edge (el und the ingle ot 15' to the horizontal muy be druwn by the edge ll, while with the instrument in the position ,ns shown in Fig'. Q, the edges (et und ll mayl be used to drew the :ingles ot 50* to the horizont-.d` diere the inside edges G und H are provided the outside edges E nnd'F niey be omitted :is indeuted in dotted lines in Fig'. l; In this inst'unee the outside edges (1 nudr D are Continued in und torni n single edge und the outline ot" the instrument would be the suine :is the lto" triangle in eonnnon use.

There is thus provided u simple, inexpensive .find symmetrical single instrument whereby all :ingles whieh ure multiples ot." 15 muy be dfruwn without the confusion to the dreftsmun which luis hereto-tore resulted in the use of those instrun'ients Where the functions of the two eonunon and (30 triangles have been combined in :L single instrument.' e

Having thus deseribed the nature and Characteristic features of my invention what I Gleim new and desire to secure by Letters Patent is l. A vdrawing instrument eon'iprisingg a thin tiet piece out suitable Inuterial having a pair of outside edges :it un angle oit 90 to each other, :mother pair of outside edges in alineinent with each other and respectively at angles of 45' 'to the first named pair of edges, und a third ptir of outside edges at. un angle of 310 to each other und respectively nt ingles 0i' 165 to the second named. pair of edges.

2. A draw-in; .instrument comprising ur thin lint piece of suitable materiel hitting' e pair of outside edges et an tingle of 90 to euch other, another lpair of outside. edges in ulinenieiit with euch other und respeetirely at :ingles of 4.50 tothe first uunied puir of' edges, and a third pair of outside edges :it :in tingle of 310 to each other und respeetively ut :ingles ot M550/to the seeond nunaed piiir ot edges, und haring its cent1-el portion out out; und provided with :L pair of interiorV 4pair of interior working edges arrzmgec't at an ongle ot' 240 to each other und respectively et :ingles of 15 tothe irst named pair of outside edges.

In testimony whereof, I have hereunto signed my neme in the presence of two witmesses.

e FREDERIC S. CRSFN.

Witnesses: y

LiLLiAN H. NEM-ina, ELIZABETH J. BLooMER. 

